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Ni abundance in the core of the Perseus Cluster: an answer to the significance of resonant scattering

Fabio Gastaldello·Silvano Molendi
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Abstract

Using an XMM-Newton observation of the Perseus cluster we show that the excess in the flux of the 7-8 keV line complex previously detected by ASCA and BeppoSAX is due to an overabundance of Nickel rather than to an anomalously high Fe He$β$/Fe He$α$ ratio. This observational fact leads to the main result that resonant scattering, which was assumed to be responsible for the supposed anomalous Fe He$β$/Fe He$α$ ratio, is no longer required. The absence of resonant scattering points towards the presence of significant gas motions (either turbulent or laminar) in the core of the Perseus cluster.

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Fabio Gastaldello, Silvano Molendi. 2003-09-22. Ni abundance in the core of the Perseus Cluster: an answer to the significance of resonant scattering. https://doi.org/10.1086/379970

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